Process for the manufacture of phenanthraquinone.



SAN ERANCISCG,

CALIFORNIA.

PBOGESS F 313, THE MANUFACQURE (3F PHENA'NTHRAQUINONE.

35o Brewing.

specification of Letters Eatent.

Application filed January 10, 1918. Serial No. 211,162?

(DEDICATED '20 THE PUEIJICJ To aZZ whom it may concern:

Be it known that we, HARRY F. Lewis and HARRY D. Gross, citizens of the United States of America, and employees of the Department of Agriculture, residing in the city of Urbana, county of Champaign, State of Illinois, and in the city 01 San Francisco, county of San Francisco, State of California. respectively (whose post-office address is Department of Agriculture, Washinston, D. (1,) have invented a new anduseful rocess for the Manufacture of Phenanthraquinone.

' This application is made under the act of March 3, 1883, chapter 143 (22 Stat. 625), and the invention herein described and claimed may be used by the Government of the United States or any of its oiiicers or employees in the prosecution of work for the Government, or any person in the United States, without payment to us of any royalty.

@ur invention relates to a process for the manufacture of phenanthraquinone from ph nanthreue.

it is well known that phenanthraquinone is commonly produced by the OXldQillOIlmOf phenanthrene in an eirtremely fine state of division by means of chromic acid. In this process the steps necessary to obtain phenanthrone of suiiicient purity are long and (iiiiicult, and furthermore, the chromic acid subsequently used for oxidation is a costly reagent. The object of our invention is to provide a process for the manufacture of phenanthraquinone which will be free from v the objectionable features of the processes employed at present.

@ur invention consists in the production of phenanthraquinone from phenanthrene by heating the phenanthrene until it passes into the vapor phase, mixing this phenanthrene vapor with an oxygen-containing gas mixture, forcing this mixture of gases into close contact with one or more of the finely divided onids of the metals of the fifth and sixth groups of the periodic system, heating to a temperature ranging from 300 C. to 550"v C, under which treatmentthe phenanthrene is partially oxidized to form the valuable product named.

To illustrate the practical operation or" our process we shall describe in detail.

' the preferred procedure.

Phenanthrene is melted and while kept in this condition it is mixed with air in excess of such an amount as is theoretically necessary to oxidize t0 phenanthraquinone whatever phenanthrene as is present in the current of air. The mixture of air and phenanthrene vapor is passed into a reaction chamber maintained at a temperature ranging from 300 C. to 550 8., the preferred temperature being 400 C. In this chamber the gas mixture is forced into close contact with one or more of the oxide of metals of the fifth and sixth groups or" the periodic system, the pentozid of vanadium is preferred, in the form of a fine powder. This powder is supported on trays or on a porous material where, by mechanical means, the current oi? mixed es is forced over or through it. lhe uses are kept under pressure only suficient to cause them to flow continuously through the reaction chamber. The products of the reaction, together with the unchanged phenanthrene, are condensed, and the phononthraquinone is separated from the unchanged phenanthrene and other substances, if any, by known processes.

. We have discovered that the process above described may be varied in a number of ways and'yet will produce henanthraquinone. Thus oxygen may die substituted wholly or in part for air, or air may be mixed with a as which is relativelyinert under the conditions obtaining in the proc ess. The oxid of-vanadium may be mixed with other substances such as asbestos, pumice stone, or other materials, and the oxids of molybdenum, dungstcn, uranium may be employed. 'ihe gas mixture may he brought in contact with or forced through the catalyst in many ways. The proportion of phenanthrene to the oxygen-containing gas mixture may be varied within wide limits. And the reaction products may be separated by various well-known means' Having thus described our invention, we claim- 1. A. process for the manufacture of phenanthraquinone, which process consists in sub ecting phenanthrene in the gaseous state and mixed with an oxygen-containing gas mixture to the actlon of the oxids oi' the subjecting phenanthrene in the gaseous state and mixed with an oxygen-containing gas mixtiu'e to the action of the oxide of the metals of the fifth and sixth groups of the periodic system, heated to temperatures ranging from 300 to 600 centigrade.

A. process for the manufacture of phenanthraquinone, which process consists in sub ecting, while in the gaseous State and mixed. with an 0-2. gen-containing gas nusv 'ture, phenanthrene, together with other substances derived from coal tar, to the action of the oxide of the metals of the fifth and sixth grouge-s of the system,'heated G. to 000 centito a temperature of 300 grade.

5. process for the manufacture of phe nanthraqninone which process consists in subjecting phenanthrene in the gaseous state and mixed with. an oxygen-containing gas nadiuin, heated to mixture to the action of peutoxid oat Jana dium, heated to temperatures ranging from 300 Qto 500 centigrae.

6. A process for the manufacture of phenanthuraquinone which process consists in subjecting phenanthrene in the and mixed with atmospheric air to the action of the pentoxici of vanadium, heated to temperatures ranging from 300 C. to 500 centigrade.

7. A process for the manufacture of phenanthraquinone, which process consists in subjecting 'phenanthrene in the gaseous state and mixed with an oxygen-containing gas mixture to the action of the pentoxidi of vatemperatures ranging from 300 (1 to 600 centigrade.

'8. A process for the manufacture of phenanthraquinone, which process consists in subjecting, while in the gaseous state and mixed with an oxygen-containing gas mixture phenanthrene, together with other substances derived from coal tar, to the action of the pentoxid of vanadium heated; to a temperature of 300 C. to 600 centigraole.

- In testimony whereof, we alhx our signatures in the presence of two subscribing witnesws.

' HARRY F. LEWIS. v HARRY D. GIBBS. Witnesses:

gaseous state 

